1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2023 Alexander V. Chernikov <melifaro@FreeBSD.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/param.h> 29 #include <sys/kernel.h> 30 #include <sys/malloc.h> 31 #include <sys/lock.h> 32 #include <sys/rmlock.h> 33 #include <sys/domain.h> 34 #include <sys/mbuf.h> 35 #include <sys/protosw.h> 36 #include <sys/proc.h> 37 #include <sys/ck.h> 38 #include <sys/socket.h> 39 #include <sys/socketvar.h> 40 #include <sys/sysent.h> 41 #include <sys/syslog.h> 42 #include <sys/priv.h> /* priv_check */ 43 44 #include <net/route.h> 45 #include <net/route/route_ctl.h> 46 47 #include <netlink/netlink.h> 48 #include <netlink/netlink_ctl.h> 49 #include <netlink/netlink_var.h> 50 #include <netlink/route/route_var.h> 51 52 /* Standard bits: built-in the kernel */ 53 SYSCTL_NODE(_net, OID_AUTO, netlink, CTLFLAG_RD, 0, 54 "RFC3549 Netlink network state socket family"); 55 SYSCTL_NODE(_net_netlink, OID_AUTO, debug, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 56 "Netlink per-subsystem debug levels"); 57 58 MALLOC_DEFINE(M_NETLINK, "netlink", "Memory used for netlink packets"); 59 60 /* Netlink-related callbacks needed to glue rtsock, netlink and linuxolator */ 61 static void 62 ignore_route_event(uint32_t fibnum, const struct rib_cmd_info *rc) 63 { 64 } 65 66 static void 67 ignore_ifmsg_event(struct ifnet *ifp, int if_flags_mask) 68 { 69 } 70 71 static struct rtbridge ignore_cb = { 72 .route_f = ignore_route_event, 73 .ifmsg_f = ignore_ifmsg_event, 74 }; 75 76 void *linux_netlink_p = NULL; /* Callback pointer for Linux translator functions */ 77 struct rtbridge *rtsock_callback_p = &ignore_cb; 78 struct rtbridge *netlink_callback_p = &ignore_cb; 79 80 81 /* 82 * nlp accessors. 83 * TODO: move to a separate file once the number grows. 84 */ 85 bool 86 nlp_has_priv(struct nlpcb *nlp, int priv) 87 { 88 return (priv_check_cred(nlp->nl_cred, priv) == 0); 89 } 90 91 struct ucred * 92 nlp_get_cred(struct nlpcb *nlp) 93 { 94 return (nlp->nl_cred); 95 } 96 97 uint32_t 98 nlp_get_pid(const struct nlpcb *nlp) 99 { 100 return (nlp->nl_process_id); 101 } 102 103 bool 104 nlp_unconstrained_vnet(const struct nlpcb *nlp) 105 { 106 return (nlp->nl_unconstrained_vnet); 107 } 108 109 #ifndef NETLINK 110 /* Stub implementations for the loadable functions */ 111 112 static bool 113 get_stub_writer(struct nl_writer *nw) 114 { 115 bzero(nw, sizeof(*nw)); 116 nw->enomem = true; 117 118 return (false); 119 } 120 121 static bool 122 nlmsg_get_unicast_writer_stub(struct nl_writer *nw, int size, struct nlpcb *nlp) 123 { 124 return (get_stub_writer(nw)); 125 } 126 127 static bool 128 nlmsg_get_group_writer_stub(struct nl_writer *nw, int size, int protocol, int group_id) 129 { 130 return (get_stub_writer(nw)); 131 } 132 133 static bool 134 nlmsg_get_chain_writer_stub(struct nl_writer *nw, int size, struct mbuf **pm) 135 { 136 return (get_stub_writer(nw)); 137 } 138 139 static bool 140 nlmsg_flush_stub(struct nl_writer *nw __unused) 141 { 142 return (false); 143 } 144 145 static void 146 nlmsg_ignore_limit_stub(struct nl_writer *nw __unused) 147 { 148 } 149 150 static bool 151 nlmsg_refill_buffer_stub(struct nl_writer *nw __unused, int required_len __unused) 152 { 153 return (false); 154 } 155 156 static bool 157 nlmsg_add_stub(struct nl_writer *nw, uint32_t portid, uint32_t seq, uint16_t type, 158 uint16_t flags, uint32_t len) 159 { 160 return (false); 161 } 162 163 static bool 164 nlmsg_end_stub(struct nl_writer *nw __unused) 165 { 166 return (false); 167 } 168 169 static void 170 nlmsg_abort_stub(struct nl_writer *nw __unused) 171 { 172 } 173 174 static bool 175 nlmsg_end_dump_stub(struct nl_writer *nw, int error, struct nlmsghdr *hdr) 176 { 177 return (false); 178 } 179 180 static int 181 nl_modify_ifp_generic_stub(struct ifnet *ifp __unused, 182 struct nl_parsed_link *lattrs __unused, const struct nlattr_bmask *bm __unused, 183 struct nl_pstate *npt __unused) 184 { 185 return (ENOTSUP); 186 } 187 188 static void 189 nl_store_ifp_cookie_stub(struct nl_pstate *npt __unused, struct ifnet *ifp __unused) 190 { 191 } 192 193 static struct nlpcb * 194 nl_get_thread_nlp_stub(struct thread *td __unused) 195 { 196 return (NULL); 197 } 198 199 const static struct nl_function_wrapper nl_stub = { 200 .nlmsg_add = nlmsg_add_stub, 201 .nlmsg_refill_buffer = nlmsg_refill_buffer_stub, 202 .nlmsg_flush = nlmsg_flush_stub, 203 .nlmsg_end = nlmsg_end_stub, 204 .nlmsg_abort = nlmsg_abort_stub, 205 .nlmsg_ignore_limit = nlmsg_ignore_limit_stub, 206 .nlmsg_get_unicast_writer = nlmsg_get_unicast_writer_stub, 207 .nlmsg_get_group_writer = nlmsg_get_group_writer_stub, 208 .nlmsg_get_chain_writer = nlmsg_get_chain_writer_stub, 209 .nlmsg_end_dump = nlmsg_end_dump_stub, 210 .nl_modify_ifp_generic = nl_modify_ifp_generic_stub, 211 .nl_store_ifp_cookie = nl_store_ifp_cookie_stub, 212 .nl_get_thread_nlp = nl_get_thread_nlp_stub, 213 }; 214 215 /* 216 * If the kernel is compiled with netlink as a module, 217 * provide a way to introduce non-stub functioms 218 */ 219 static const struct nl_function_wrapper *_nl = &nl_stub; 220 221 void 222 nl_set_functions(const struct nl_function_wrapper *nl) 223 { 224 _nl = (nl != NULL) ? nl : &nl_stub; 225 } 226 227 /* Function wrappers */ 228 bool 229 nlmsg_get_unicast_writer(struct nl_writer *nw, int size, struct nlpcb *nlp) 230 { 231 return (_nl->nlmsg_get_unicast_writer(nw, size, nlp)); 232 } 233 234 bool 235 nlmsg_get_group_writer(struct nl_writer *nw, int size, int protocol, int group_id) 236 { 237 return (_nl->nlmsg_get_group_writer(nw, size, protocol, group_id)); 238 } 239 240 bool 241 nlmsg_get_chain_writer(struct nl_writer *nw, int size, struct mbuf **pm) 242 { 243 return (_nl->nlmsg_get_chain_writer(nw, size, pm)); 244 } 245 246 bool 247 nlmsg_flush(struct nl_writer *nw) 248 { 249 return (_nl->nlmsg_flush(nw)); 250 } 251 252 void nlmsg_ignore_limit(struct nl_writer *nw) 253 { 254 _nl->nlmsg_ignore_limit(nw); 255 } 256 257 bool 258 nlmsg_refill_buffer(struct nl_writer *nw, int required_len) 259 { 260 return (_nl->nlmsg_refill_buffer(nw, required_len)); 261 } 262 263 bool 264 nlmsg_add(struct nl_writer *nw, uint32_t portid, uint32_t seq, uint16_t type, 265 uint16_t flags, uint32_t len) 266 { 267 return (_nl->nlmsg_add(nw, portid, seq, type, flags, len)); 268 } 269 270 bool 271 nlmsg_end(struct nl_writer *nw) 272 { 273 return (_nl->nlmsg_end(nw)); 274 } 275 276 void 277 nlmsg_abort(struct nl_writer *nw) 278 { 279 _nl->nlmsg_abort(nw); 280 } 281 282 bool 283 nlmsg_end_dump(struct nl_writer *nw, int error, struct nlmsghdr *hdr) 284 { 285 return (_nl->nlmsg_end_dump(nw, error, hdr)); 286 } 287 288 int 289 nl_modify_ifp_generic(struct ifnet *ifp, struct nl_parsed_link *lattrs, 290 const struct nlattr_bmask *bm , struct nl_pstate *npt) 291 { 292 return (_nl->nl_modify_ifp_generic(ifp, lattrs, bm, npt)); 293 } 294 295 void 296 nl_store_ifp_cookie(struct nl_pstate *npt, struct ifnet *ifp) 297 { 298 return (_nl->nl_store_ifp_cookie(npt, ifp)); 299 } 300 301 struct nlpcb * 302 nl_get_thread_nlp(struct thread *td) 303 { 304 return (_nl->nl_get_thread_nlp(td)); 305 } 306 307 #endif /* !NETLINK */ 308 309